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161.
162.
In horticultural practice accelerated plant development and particularly earlier flowering, has been reported with microalgae applications. Therefore, the objective of this work was to study the effects of foliar spraying with Scenedesmus sp. and Arthrospira platensis hydrolysates on Petunia x hybrida plant development and leaf nutrient status. Three treatments were tested: T1 (foliar application with water, the control), T2 (foliar application with Arthrospira), and T3 (foliar application with Scenedesmus). Foliar spraying was applied five times (0, 14, 28, 35, and 42 days after transplanting). The concentration of both microalgae was 10 g L?1. At the end of the trial biometric parameters and nutrient concentration in photosynthetic organs (the leaves) were measured. The results of this assay show that foliar application of Scenedesmus accelerated plant development in terms of higher rates of root growth, leaf and shoot development, and earliness of flowering. Arthrospira enhanced the root dry matter, the number of flowers per plant, and the water content. Nevertheless, a reduction was found in the conductive tissue (stem + petiole) dry weight with Arthrospira compared with Scenedesmus and the control. The results also show that microalgae hydrolysate supply can improve the plant nutrient status. Based on these results, it is advisable to use Scenedesmus hydrolysates in foliar applications to increase the blooming of Petunia x hybrida.  相似文献   
163.
Summary A crude extract of Alcaligenes sp. CPE3 strain grown on 3,4-dichlorobenzoic acid metabolised 3- and 4-chlorobenzoic acid by reactions requiring O2 and NADH, and 3,4-dichlorobenzoic acid by a reaction requiring O2, NADH, FAD and FMN. The specific activity of the extract vs. 3-chlorobenzoic acid was described by the Michaelis-Menten kinetics, that vs. 4-chlorobenzoic acid was described by a substrate inhibitory kinetics and that vs. 3,4-dichlorobenzoic acid exhibited a two-peaked profile.  相似文献   
164.
The prevalence ofM. furfur, a lipodependent fungus, in the skin of 0 to 15-year-old healthy children was studied. Sterilized carpet was used to collect skin samples which were cultured in Oxgall medium (Difco) with 1% olive oil and incubated for 10 days at 37 °C.M. furfur was recovered in 17.8% of infants, with similar findings in both sexes. The highest prevalence ofM. furfur colonization was found among children of 0 to 18 months and 11 to 15-year-olds, with 23.3% and 26.7% respectively.Part of the Ms. thesis of Victor Silva Associação deMalassezia furfur com patologias com componente seborréico.  相似文献   
165.
We investigated NADH oxidation in non-synaptic and synaptic mitochondria from brain cortex of 4- and 24-month-old rats. The NADH oxidase activity was significantly lower in non-synaptic mitochondria from aged rats; we also found a significant decrease of sensitivity of NADH oxidation to the specific Complex I inhibitor, rotenone. Since the rotenone-binding site encompasses Complex I subunits encoded by mtDNA, these results are in accordance with the mitochondrial theory of aging, whereby somatic mtDNA mutations are at the basis of cellular senescence. Accordingly, a 5 kb deletion was detected only in the cortex of the aged animals.  相似文献   
166.
The mitochondrial genome of animals encodes a few subcomponents of the respiratory chain complexes I, III and IV, whereas nuclear DNA encodes the overwhelming majority, both in quantitative and qualitative terms, of mitochondrial proteins. Complete depletion of mitochondrial DNA (mtDNA) can be achieved by culturing cells in the presence of inhibitors of mtDNA replication or mitochondrial protein synthesis, giving rise to mutant cells (ϱ∘ cells) which carry morphological near-to-intact mitochondria with respiratory defects. Such cells can be used to study the impact of mitochondrial respiration on apoptosis. ϱ∘ cells do not undergo cell death in response to determined stimuli, yet they conserve their potential to undergo full-blown apoptosis in many experimental systems. This indicates that mtDNA and associated functions (in particular mitochondrial respiration) are irrelevant to apoptosis execution. However, the finding that mtDNA-deficient mitochondria can undergo apoptosis does not argue against the involvement of mitochondria in the apoptotic process, since mitochondria from ϱ∘ cells conserve most of their functions including those involved in the execution of the death programme: permeability transition and release of one or several intermembrane proteins causing nuclear apoptosis. Supported by ARC, ANRS, CNRS, FRM, Fondation de France, INSERM, NATO, Ligue contre le Cancer Ministère de la Recherche et de l'Industrie (France), and Sidaction (to GK). SAS receives a fellowship from the Spanish Government (Ministerio de Ciencia y Educación).  相似文献   
167.
d-Serine is the co-agonist of NMDA receptors and binds to the so-called glycine site. d-Serine is synthesized by human serine racemase (SR). Over activation of NMDA receptors is involved in many neurodegenerative diseases and, therefore, the inhibition of SR might represent a novel strategy for the treatment of these pathologies. SR is a very difficult target, with only few compounds so far identified exhibiting weak inhibitory activity. This study was aimed at the identification of novel SR inhibitor by mimicking malonic acid, the best-known SR inhibitor, with a cyclopropane scaffold. We developed, synthesized, and tested a series of cyclopropane dicarboxylic acid derivatives, complementing the synthetic effort with molecular docking. We identified few compounds that bind SR in high micromolar range with a lack of significant correlation between experimental and predicted binding affinities. The thorough analysis of the results can be exploited for the development of more potent SR inhibitors.  相似文献   
168.
Environmental Biology of Fishes - In the Central Valley of California, environmental characteristics differ between perennial and ephemeral stream types and therefore present different challenges...  相似文献   
169.
Two species of Melissa are currently present in Sardinia: Melissa officinalis L. and Melissa romana Mill . Our research can only count on a few supported evidences (as reported in Flora Italiana and Moris) and some notes on new stations in Sardinia that give us some information about morphology, distribution, bioecological, and ethnobotanical characteristics of both species. In this paper, we present the results of the research about morphological aspects of Mromana vs. Mofficinalis, and their essential oils in different stations at different phenological periods. Moreover, we compared the essential oil of Mromana with the one obtained from Mofficinalis growing in the few naturalized stations still present in Sardinia. The most evident morphological differences between the two entities are the long‐stalked capitate glandular trichomes, shorts and inclined capitate trichomes, and peltate hairs. The chemical composition of essential oil presents several significant differences between the species. In fact, oils show that in none of the phenological stages, M. romana recalls in its composition M. officinalis. Major distinctions are also evident between dry and fresh plants, and among essential oils distilled in different seasons.  相似文献   
170.
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